Sender's email address is broken after importing a PST file into an Exchange Server 2013 mailbox

Symptoms

You import a PST file to a Microsoft Exchange Server 2013 mailbox by running the New-MailboxImportRequest Windows PowerShell cmdlet.

You open the mailbox in Microsoft Outlook, and then you try to reply to an email message that was imported from the PST file.

In this scenario, the display name of the sender of the original email is in the To field. However, the display name does not contain the SMTP address.

Cause

This issue occurs because the Exchange store does not add a certain property automatically when email messages are copied from a PST file. Therefore, Outlook cannot import recipients' information correctly.